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都山花岗岩体是冀东地区最大的花岗岩基,在其周边产有众多与其有关的“卫星”岩体和岩脉。采用先进的SHRIMP定年方法,测得都山花岗岩基的206Pb/238U年龄为(223±2)Ma,其东侧三家金矿区成矿前花岗斑岩脉的年龄为(222±4)Ma,二者在误差范围内一致,花岗岩基和花岗斑岩脉可视为同一次岩浆活动的产物。这种晚古生代末—早中生代印支期的花岗岩在华北克拉通北缘广泛分布,显示它是一次重要的构造-岩浆事件的产物。根据岩石化学和微量元素特征及有关判别图,都山等印支期花岗岩可能属中朝板块与西伯利亚板块碰撞造山作用的后碰撞花岗岩。花岗斑岩脉中发现有新太古代的继承锆石,表明花岗斑岩的部分源岩为区内新太古代八道河岩群变质岩。都山花岗岩与花岗斑岩脉同时、同源,推测其源岩也有部分为新太古代结晶基底的变质岩。花岗岩与区内金矿化有较大的时差,两者不存在直接的成因联系,仅表明成矿晚于早中生代印支期。
Dushan granite body is the largest granite base in eastern Hebei Province, in its periphery there are many related to its “satellite” rock and dikes. Using the advanced SHRIMP dating method, the 206Pb / 238U age of the Dushan granite basement is (223 ± 2) Ma, and the age of the ore-forming granite porphyry vein in the Sanjia gold deposit area to the east is (222 ± 4) Ma , Which are consistent within the error range. Granite base and granite porphyry veins can be regarded as the product of the same magmatic activity. This late Paleozoic-early-Mesozoic Indosinian granite is widely distributed in the northern margin of North China Craton, indicating that it is an important tectono-magmatic event. Based on the characteristics of petrochemistry and trace elements and related discriminant maps, Indosinian granites such as Dushan may belong to post-collision granite collision between the North China Plate and Siberian plate. New granitic porphyry veins found in the new Archean inherited zircon, indicating that part of the granite porphyry source rocks for the new Archean Ba Daohe Group metamorphic rocks. Dushan granite and granite porphyry vein at the same time, homology, it is speculated that some of its source rocks for the Neo-Archean crystalline basement metamorphic rocks. There is a large time difference between granite and gold mineralization in the area. There is no direct genetic correlation between the granite and the gold mineralization in the area, indicating that the mineralization is later than that of the early Mesozoic Indosinian.